1. Field of the Invention
The present invention relates to a water-disintegrable paper and a process for producing the same, and in particular it is related to a water-disintegrable paper having moisture retaining property which is useful as a toilet paper or a sanitary paper for wiping babies' bottoms, and which can be disposed of by flushing in an ordinary water closet and the like.
2. Description of the Related Art
In the past, a flushable cleansing tissue comprising a water-disintegrable paper impregnated with cosmetic oily raw materials and a surfactant (Japanese Unexamined Patent Publication No. 59-144426), a paper product for cleaning a hemorrhoidal skin comprising a low density tissue paper treated with a softening oil agent (Japanese Unexamined Patent Publication No. 62-87117), and a skin cleansing/cleaning material comprising a water-disintegrable paper containing eucalyptus pulp which is impregnated with oil components (Japanese Unexamined Patent Publication No. 4-15021) have been introduced as a cleaning and cleansing paper product having water-disintegrability (solubility or dispersibility in water).
Also, cleaning/cleansing agent compositions having a predetermined viscosity and containing silicone oil and a lower alcohol (Japanese Unexamined Patent Publication No. 62-135415), an anal part cleaning/cleansing agent comprising an aqueous solution containing a surfactant and an alcohol as main ingredients (Japanese Unexamined Patent Publication No. 62-242611), cleaning/cleansing compositions containing polyoxyalkylene modified organopolysiloxane (Japanese Unexamined Patent Publication No. 64-83014) and other products have been known and these products have been proposed to be used by spraying them on a toilet paper or by spraying them directly on the specific part.
Furthermore, a toilet paper comprising a water-soluble paper impregnated with a liquid solution containing water or an alcohol, a perfume and a solute for disinfection such as glycerol (Japanese Unexamined Patent Publication No. 4-325129) has been known as well.
With those paper products disclosed in the publications of the above-mentioned Japanese Unexamined Patent Publication Nos. 59-144426, 62-87117, and 4-15021, the water disintegrability, the dirt wiping out property, and the skin protecting property are improved while the dry paper strength of the toilet paper, which inherently should not have wet paper strength, is prevented from being lowered. But, the above-mentioned paper products have been inconvenient as they might let hands and toilet bowls besmeared during the use, and their feel and the wiping out property have been far from the satisfactory level.
In addition, though the toilet paper impregnated with oils and the like have been accepted by those specific patients who are, for example, suffering from inflammation around the anal part, ordinary people are still reluctant to use those products, accordingly they are not yet in general use.
Those cleansing/cleaning agents disclosed in the publications of Japanese Unexamined Patent Publication Nos. 62-135415, 62-242611, and 64-83014 are used by spraying them on a toilet paper, or by spraying them directly on the anal part and the like, followed by wiping with a toilet paper. But, such a use form is complicated as it needs step-wise application, and it is particularly unsuitable for the aged and toddlers to use by themselves.
The toilet paper disclosed in the publication of Japanese Unexamined Patent Publication No. 4-325129 needs to be cased in a container made of a material having moisture-proof property so that the water-soluble paper shall not be dried by the evaporation of the solvent solution, and this leads to the increase of the production cost.
In addition, since this type of toilet paper is supposed to be used after the conventional toilet paper is used to wipe out the dirt, its use has been troublesome and time-consuming.